Veneault-Fourrey Claire, Lambou Karine, Lebrun Marc-Henri
University of Exeter, School of Biosciences, Washington Singer Laboratories, Exeter, UK.
FEMS Microbiol Lett. 2006 Mar;256(2):179-84. doi: 10.1111/j.1574-6968.2006.00128.x.
The ability of plant pathogenic fungi to infect their host depends on successful penetration into plant tissues. This process often involves the differentiation of a specialized cell, the appressorium. Signalling pathways required for appressorium formation are conserved among fungi. However, the functions involved in appressorium maturation and penetration peg formation are still poorly understood. Recent studies have shown that Pls1 tetraspanins control an appressorial function required for penetration into host plants and are likely conserved among plant pathogenic fungi. Tetraspanins are small membrane proteins widely distributed among ascomycetes and basidiomycetes defining two distinct families; Pls1 tetraspanins are found in both ascomycetes and basidiomycetes and Tsp2 tetraspanins are specific to basidiomycetes. Both fungal tetraspanins families have similar secondary structures shared with animal tetraspanins. Pls1 tetraspanins are present as single genes in genomes of ascomycetes, allowing a unique opportunity to study their function in appressorium mediated penetration. Experimental evidence suggests that Pls1 tetraspanins are required for the formation of the penetration peg at the base of the appressorium, probably through re-establishing cell polarity.
植物病原真菌感染宿主的能力取决于能否成功穿透植物组织。这一过程通常涉及一种特殊细胞——附着胞的分化。附着胞形成所需的信号通路在真菌中是保守的。然而，附着胞成熟和侵入栓形成所涉及的功能仍知之甚少。最近的研究表明，Pls1四跨膜蛋白控制着侵入宿主植物所需的附着胞功能，并且可能在植物病原真菌中保守存在。四跨膜蛋白是一类小的膜蛋白，广泛分布于子囊菌和担子菌中，分为两个不同的家族；Pls1四跨膜蛋白在子囊菌和担子菌中均有发现，而Tsp2四跨膜蛋白则是担子菌特有的。真菌的这两个四跨膜蛋白家族都具有与动物四跨膜蛋白相似的二级结构。Pls1四跨膜蛋白在子囊菌基因组中以单基因形式存在，这为研究它们在附着胞介导的穿透过程中的功能提供了独特的机会。实验证据表明，Pls1四跨膜蛋白可能通过重新建立细胞极性，在附着胞基部形成侵入栓的过程中发挥作用。
